Estudo da calcinação de calcário para a produção de óxido de cálcio

Abstract

Waste management has become a problem for the mining industry over the years, since agricultural spaces and even environmental protected areas are used for the accumulation of these materials. Therefore, a lot of research effort has been applied to find ways to use and characterize waste generated mining companies, especially those with the potential for transformation into product / by-products. Most of the existing studies in the literature about the calcination and characterization of limestone were performed using samples with large average particle sizes. Thus, in this study, the calcination of a residue rich in calcitic limestone of smaller granulometries was evaluated. The calcination reaction of calcitic limestone aiming the production of calcium oxide (CaO) and magnesium oxide (MgO) was designated as one of the recovery route of this residue. This study is divided in two parts, the first one is related to the characterization of samples 1, 2 and 3 conducting tests as thermogravimetric analysis, reactivity, X-ray diffraction and loss on ignition in order to find the best calcination conditions to obtain a quality lime and the second part is to obtain the optimum calcination temperature, by conducting calcination, reactivity and loss on ignition tests carried out for the sample with the best reactivity at part one (sample 2). Through the experiments developed, an optimum calcination temperature of 900 ° C was obtained. The loss on ignition values were between 2.6 and 3.94%. The obtained calcination efficiencies were between 89.39 and 93.04%.